Technical Booklet E Fire Safety·Page 136·Table 5.1A notes (2) and (3)
Acceptable alternatives for external wall materials
Profiled or flat steel sheet and timber cladding are acceptable alternatives to meeting the standard fire classifications under specified conditions.
(2) Profiled or flat steel sheet at least 0.5mm thick with an organic coating of no more than 0.2mm thickness is also acceptable. (3) Timber cladding at least 9mm thick is also acceptable.
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